1. Field of Invention:
The present invention relates to snow poles which can be installed in connection with an existing delineator along a road side, particularly where snow accumulations can exceed the height of the delineator and thereby obscure its vision.
More specifically, the present invention relates to removable snow poles which can be installed or withdrawn in accordance with the seasons.
2. Prior Art:
Highway delineation devices are an integral part of virtually every well-traveled roadway. This is particularly true at curved sections of the road where night receptors mounted to delineators provide advance warning to motorists of a change of direction.
The most common delineator device on the open highway is generally referred to as a "hat-section" post. This name was acquired by its association with the hat-like cross-section of the post, as is illustrated in FIGS. 1 and 3. The post is typically fabricated of steel and includes two side walls 10 and 11, each having a mounting flange 12 and 13 to facilitate attachment of a reflector plate 14. These respective side walls 10 and 11 and flanges 12 and 13 resemble a side view of a hat, with the top of the hat being formed by the back plate 15. The interior of the hat would be comparable to the channel 16 formed between side walls 10 and 11.
These delineators vary in length from five to seven feet and are positioned along the road side at a height of approximately four to five feet above ground level. The reflective plate 14 may extend from three to 12 inches in length, defining a tubular enclosure 16a formed in combination with the channel 16. The channel configuration for the hat-section post closely resembles a trapezoid with side walls 10 and 11 and primary and secondary bases formed by reflector plate 14 and back plate 15. The elevation of the reflector plate 14 at approximately four feet provides correct angular orientation with respect to headlight reflection for night travelers.
During winter seasons, snow accumulations may exceed the height of the delineator and thereby obscure both day and night view of the delineator structure. Such snow accumulation may be by natural snowfall or snow drifting, or may be piled along the road side by snow plows during normal operation. In any event, concealment of the subject delineation devices poses extreme hazards to the driver, particularly at night.
Accordingly, it has been common practice to attach a snow pole extension to give added height to the delineator. Typically, this is done by utilizing a slat or rod which is somehow anchored to the existing delineator (such as the hat section of FIG. 1). This rod may extend to any desired height above the delineator, depending upon expected snow accumulation. Methods of attaching the snow pole to the delineator have varied from merely inserting of the rod or strap into the tubular opening 16a and extending channel in a "free-moving" manner, or by bolting or wiring the snow pole to the delineator body for more secure positioning.
These respective methods each have disadvantages which represent increased expense in connection with maintenance of a snow pole system. For example, utilization of a strap bolted to the delineator body is labor intensive, requiring significant effort to insert and tighten bolts through properly aligned holes in the snow pole and delineator. Also, vibration in the strap body arising from constant wind buffeting causes the strap to wear and fail at the bolted location. When one considers the hundreds of thousands of delineators which require snow pole extensions, the extreme cost of making such modifications or affecting repair becomes significant. In contrast, if the snow pole is merely inserted in free-moving manner, it is easily stolen, or may be knocked free by action of a snow plow, wind or incidental contact with projecting objects from trucks and other vehicles. Finally, and most important, public safety demands that the risk of injury or loss of human life be minimized by proper delineation. Accordingly, the seriousness of maintaining effective delineation despite snow accumulation and/or removal becomes even more serious.